@yaser-az If there are no products in your database then you would not be able to see anything in datagrid.
But an empty table looks like the shot below:
The screenshot you posted neither shows your product index page nor the browser console at that stage.
And I want to know if you create products then can you see results in your product grid.

I managed to solve the problem by duplicating the package.json from the 'packages/Webkul/Ui' package and run npm install and all the steps that karkiswapnil gave in his solution.
i recommend to not update packages but to use the same versions even if it warns you about vulnerability, otherwise you won't be able to follow the step by step of the documentation.
And please review your own 'package develop documentation, from the step 9 it starts to be a little confusing and redundant with the folder structure, you should upload the ideal folder structure for the helloworld package, thanks

https://forums.bagisto.com/assets/uploads/files/1565077566209-screenshot-98.png
There is no load property defined in Standard Controller that's why you getting Undefined Property Exception.
https://forums.bagisto.com/assets/uploads/files/1565077547818-screenshot-100.png
There is no need to call parent constructor, please remove the following line:
parent::__construct();

Hi,
If you want to create your own custom asset, then inside theme packages helper function, you can create your own function as we did.
function bagisto_asset($path, $secure = null)
{
return themes()->url($path, $secure);
}
After creating this function, you can use it according to your need.
Thanks
Rahul Shukla